Effects of Quantum Deformations on the Spectrum of Cosmological Perturbations

We consider a quantum deformation of the wave equation on a cosmological background as a toy-model for possible trans-Planckian effects. We compute the power spectrum of scalar and tensor fluctuations for power-law inflation, and find a noticeable deviation from the standard result. We consider de Sitter inflation as a special case, and find that the resulting power spectrum is scale invariant. For both inflationary scenarios the departure from the standard spectrum is sensitive to the size of the deformation parameter. A modulation in the power spectrum appears to be a generic feature of the model.